1. Field of the Invention
The present invention relates to an electromagnetic interference shielding apparatus for a signal transceiver. More particularly, the present invention relates to an electromagnetic interference shielding apparatus applicable to a high-frequency signal transceiver.
2. Description of the Related Art
Generally speaking, if is difficult for microwave signals transmitted between the earth and artificial satellites to pass through walls, roofs, or even glass windows. Therefore, satellite signal transceivers are located outdoors with antennas pointing directly at artificial satellites to obtain optimal transmission efficiencies. FIG. 1(a) shows a conventional shielding apparatus 10 of a block upconverter (BUC) accommodating an outdoor satellite signal transceiver (not shown), which is mainly used to protect the outdoor satellite signal transceiver from damage caused by the external environment (e.g., rain, moisture, etc.). FIG. 11(b) is a partial cross-sectional view of the shielding apparatus 10. The shielding apparatus 10 includes an upper cover 11, a chassis 12, and a waveguide output hole (not shown). When the shielding apparatus 10 is applied to protect the outdoor satellite signal transceiver, the outdoor satellite signal transceiver is placed in an internal space 15 formed by the cover 11 and the chassis 12. To enable the satellite signal transceiver to be used outdoors and be waterproof, the shielding apparatus 10 utilizes an O-ring 13 disposed between the cover 11 and the chassis 12, and employs a plurality of screws 14 to combine the cover 11 and the chassis 12. Meanwhile, pressure is applied to the O-ring 13 to deform the O-ring 13, thus realizing the waterproof function. However, the conventional shielding apparatus 10 has the following disadvantages: (1) the cover 11 and the chassis 12 are generally fabricated by die casting; when they are combined by the plurality of screws 14 and the O-ring 13, the slit between rough combined surfaces 111 and 121 cannot effectively stop the leakage of high-frequency signals (e.g., signals belonging to the Ku band, C band, or Ka band), and cannot effectively shield the interference of external noises; and (2) when disassembling or assembling the upper cover 11 and the chassis 12, the screws 14 must be loosened or fastened one by one, so much time and cost has to be spent during assembly and testing.